Product Name: Magnetic Paper/Magnetic Field Viewing Film /Magnetic Field Viewer/Magnetic Field Demonstrator Film Size: 4″”x 4″”(L*W) Color: Brownish Yellow Material: magnetic nanoparticles Features: Clearly observe the patterns of the magnetic field. Place the film as close as possible to the magnet/item to observe the pattern changes. Reusable and automatic recovery. The stronger magnets, the better the results. Warmming Tips: We are committed to making excellent products, if you are not satisfied with your order, please feel free to contact us for good solutions. Package includes: 1 x Magnetic viewing film